As is known, photomodification can be brought about by photochemical initiation. This so called photomodification has many applications, e.g. in fiber production, curing of lacquers or production of printing plates. For the purpose of this description, polymers or composition of polymer which are photochemically modified by polarized light will be called "photopolymers".
It is also known that in the so-called stretching of thermoplasties to increase their strength, the molecules in the amorphous regions are given a parallel alignment. The alignment can be fixed, e.g. by cooling, to produce oriented polymers. Other methods of producing oriented polymers are also known, e.g. uniform alignment in an electric field during photomodification, provided the monomer contains an electric dipole. Still another method is to mechanically brush polymers to achieve alignment.